Activity Budgets, feeding behavior, and habitat use of pygmy chimpanzees at Lomako, Zaire

Data from 250 hours of focal animal sampling in the Lomako Forest of central Zaire show pygmy chimpanzees spent 70% of feeding time on fruit and 25% on young leaves. Feeding and resting each accounted for about 40% and traveling less than 20% of the time. Sitting was the most frequent feeding posture. Locomotion was predominantly quadrupedal walking and quadrumanous climbing. Most feeding and resting occurred above 30 m. Pygmy chimpanzees spent most time in primary forest. Activity budgets varied with forest type. Most levels were used in each forest type. Pygmy chimpanzees spent most time in the canopy when in primary and slope (Bolafa) forests, and on the ground in secondary forest. These results show pygmy chimpanzees as arboreal, but habituation may have influenced the results. Pygmy chimpanzees at Lomako and Wamba have similar diets, despite differences in methods of data collection. At Wamba and Lomako, pygmy chimpanzees use secondary forest more and swamp forest less than expected given the abundance of each forest type at both sites.